@dazzling-plumber-90795 this should now be fixed:

$ curl -sSL <https://binaries.pantsbuild.org/> | xmllint --format - | grep ab51a617f069641eb6b47e8713e51150ad0a6ab0
    <Key>bin/native-engine/linux/x86_64/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.10/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.11/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.12/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.13/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.7/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.8/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>
    <Key>bin/native-engine/mac/10.9/ab51a617f069641eb6b47e8713e51150ad0a6ab0/native_engine.so</Key>

Filed https://github.com/pantsbuild/pants/issues/5061 to track a general fix for 1.3.X, releases of which which will continually run into this issue if left as-is.